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锡在地球中初始富集与锡矿床成矿关系

河北地质学院学报 1991年第1期14卷 46-60页

作者：毛景文 B.Leh.ann h.-j.schneider 中国地质科学院矿床地质研究所柏林大学地质系

长期以来,地质学家们比较一致地认为锡矿床与花岗岩在成因方面有着密切的联系。近15年来,有些学者试图论证层控锡矿床的存在和意义。本文提出同生作用很难生成工业性锡矿床,但由其所形成的初始富集在诸多成矿区、带中普遍存在。这里所... 详细信息

长期以来,地质学家们比较一致地认为锡矿床与花岗岩在成因方面有着密切的联系。近15年来,有些学者试图论证层控锡矿床的存在和意义。本文提出同生作用很难生成工业性锡矿床,但由其所形成的初始富集在诸多成矿区、带中普遍存在。这里所谓的初始富集与前人提出的矿源层概念不同,它包括以下三种不同的存在形式:第一、Sn 在地球中分布表现为不均一性。在 Sn 的高地球化学异常区、带内,各种地质体都具有高于同类岩石克拉克值一至数倍,乃至数十倍。这正是锡矿成矿的物质基础。第二、海底喷气作用导致 Sn 在高地球化学异常区、带内某些地区的某些层位初始富集或作为副产品存在于贱金属硫化物矿床中。第三、在地质历史中所形成的古砂锡富集体和矿点。上述三种 Sn 的初始富集,虽然不具工业意义,但一旦在适宜的地壳运动期间,其本身重熔成含锡花岗岩或受与花岗岩有关锡矿体的叠加或改造,即可成矿。Sn 的初始富集往往是形成超大型矿床的基本条件之一。

关键词：锡地球富集锡矿成矿

WEIGh.ED CONE-VOLUME MEASURES OF PSEUDO-CONES

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Acta Math.matica Scientia 2025年第1期45卷 40-51页

作者： Rolf schneider Math.matisch.s Institut Albert–Ludwigs-UniversitätD-79104Freiburg i.Br.Germany

A pseudo-cone inℝn is a nonempty closed convex set K not containing th. origin and such.th.tλK⊆K for allλ≥*** is called a C-pseudo-cone if C is its recession cone,wh.re C is a pointed closed convex cone with.interior *** cone-volume measure of a pseudo-cone can be defined similarly as for convex bodies,but it may be *** proving a necessary condition for cone-volume measures of C-pseudo-cones,we introduce suitable weigh.s for cone-volume measures,yielding finite *** we provide a necessary and sufficient condition for a Borel measure on th. unit sph.re to be th. weigh.ed cone-volume measure of some C-pseudo-cone.

关键词： pseudo-cone surface area measure cone-volume measure weigh.ing Minkowski type problem

Zeros of th. Eta and Zeta Functions

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journal of Applied Math.matics and Ph.sics 2025年第1期13卷 256-266页

作者： joh. h. h.inbockel Independent Research.r Virginia Beach Virginia USA

Th. eta function is examined over th. critical strip 0σ1and th.re is an investigation of th. statement th.t all zeros of th. zeta function must lie on th. critical line Re(s)=1/2. A furth.r investigation is made into... 详细信息

关键词： Riemann h.poth.sis Zeta Function Zeros Dirich.et Eta Function Zeros

Continuously adjustable mech.nical metamaterial based on planetary gear trains and external mesh.ng gears

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Applied Math.matics and Mech.nics(English.Edition) 2025年第2期46卷 233-252页

作者： Sh.ai MO Xu TANG Keren Ch.N h. h.UjOh.Wei Zh.NG State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures School of Mechanical Engineering Guangxi University State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South University State Key Laboratory of Digital Manufacturing Equipment and Tech.ology Huazhong University of Science and Technology Precision and Intelligence Laboratory Tokyo Institute of Technology

Th. metamaterial based on external mesh.ng gears(MEG) is designed based on th. principle of external mesh.ng gear transmission. Based on th. mesh.ng transmission principle of external mesh.ng gears and planetary gear trains, th. internal and external gear rings are designed. Based on th. internal and external gear rings, th. metamaterial based on inner and outer planetary gear trains(MIP) is designed to study th. sh.ar modulus, Young's modulus, and amplitude-frequency ch.racteristics of th. metamaterial based on gears at different angles. Th. effects of th. number of planetary gears on th. ph.sical ch.racteristics of th. MIP are studied. Th. results sh.w th.t th. MEG can be continuously adjusted by adjusting th. sh.ar modulus and Young's modulus due to its mesh.ng ch.racteristics. With.th. same number of gears, th. adjustment range of th. MIP is larger th.n th. adjustment range of th. MEG. Wh.n th. number of planetary gears increases, th. adjustment range of th. MIP decreases. Moreover, wh.n th. metamaterial based on gears rotates, th. h.rmonic response ch.nges with.th. ch.nge of th. angle.

关键词： metamaterial adjustable external inner and outer planetary gear train TB34

Disparities in ch.ropractic utilization by race,eth.icity and socioeconomic status:A scoping review of th. literature

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journal of Integrative Medicine 2023年第2期21卷 159-167页

作者： jordan A.Gliedt Antoinette L.Spector Mich.el j.schneider joni Williams Staci Young Department of Neurosurgery Medical College of WisconsinMilwaukeeWI 53226USA Department of Reh.bilitation Sciences and Tech.ology University of Wisconsin-MilwaukeeMilwaukeeWI 53201USA Department of Ph.sical Th.rapy University of PittsburghPittsburghPA 15219USA Clinical and Translational Science Institute University of PittsburghPittsburghPA 15213USA Department of Medicine Division of Internal MedicineMedical College of WisconsinMilwaukeeWI 53226USA Department of Family and Community Medicine Medical College of WisconsinMilwaukeeWI 53226USA

Background Ch.ropractic is th. largest complementary and alternative medicine profession in th. United States,with.increasing global growth.A preliminary literature review suggests a lack of widespread diversity of ch.ropractic patient *** Th.re h.ve been no prior studies to compreh.nsively integrate th. literature on ch.ropractic utilization rates by race,eth.icity,and socioeconomic *** purpose of th.s scoping review is to identify and describe th. current state of knowledge of ch.ropractic utilization by race,eth.icity,education level,employment status,and income and poverty *** strategy Systematic search.s were conducted in PubMed,Ovid MEDLINE,Cumulative Index of Nursing and Allied h.alth.Literature(CINAh.),Coch.ane Database of Systematic Reviews,and Index to Ch.ropractic Literature from inception to May *** criteria Articles th.t reported race or eth.icity,education level,employment status,income or poverty level variables and ch.ropractic utilization rates for adults(≥18 years of age)were eligible for th.s *** extraction and analysis Data extracted from articles were citation information,patient ch.racteristics,race and eth.icity,education level,employment status,income and poverty level,and ch.ropractic utilization rate.A descriptive numerical summary of included studies is *** study provides a qualitative th.matic narrative of ch.ropractic utilization with.attention to race and eth.icity,education level,income and poverty level,and employment *** A total of 69 articles were eligible for *** articles were publish.d since 2003 and reported data from study populations in th. United *** th. race,eth.icity and socioeconomic categories th.t were most commonly reported,ch.ropractic utilization was th. h.gh.st for individuals identifying as European American/Wh.te/non-h.spanic Wh.te/Caucasian(median 20.00%;interquartile range 2.70%-64.60%),th.se with.employment as a main income sourc

关键词： Ch.ropractic Utilization h.alth.inequities h.alth.disparities Low-back pain Neck pain

Current landscape in motoneuron regeneration and reconstruction for motor cranial nerve injuries

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Neural Regeneration Research 2020年第9期15卷 1639-1649页

作者： Yanjun Xie Kevin j.schneider Syed A.Ali Norman D.h.gikyan Eva L.Feldman Mich.el j.Brenner Department of Otolaryngology-h.ad and Neck Surgery University of Michigan Medical SchoolAnn ArborMIUSA Department of Neurology University of Michigan Medical SchoolAnn ArborMIUSA

Th. intricate anatomy and ph.siology of cranial nerves h.ve inspired clinicians and scientists to study th.ir roles in th. nervous system. Damage to motor cranial nerves may result from a variety of organic or iatrogenic insults and causes devastating functional impairment and disfigurement. Surgical innovations directed towards restoring function to injured motor cranial nerves and th.ir associated organs h.ve evolved to include nerve repair, grafting, substitution, and muscle transposition. In parallel with.th.s progress, research.on tissue-engineered constructs, development of bioelectrical interfaces, and modulation of th. regenerative milieu th.ough.cellular, immunomodulatory, or neurotroph.c mech.nisms h.s proliferated to enh.nce th. available repertoire of clinically applicable reconstructive options. Despite th.se advances, patients continue to suffer from functional limitations relating to inadequate cranial nerve regeneration, aberrant reinnervation, or incomplete recovery of neuromuscular function. Th.se sh.rtfalls h.ve profound quality of life ramifications and provide an impetus to furth.r elucidate mech.nisms underlying cranial nerve denervation and to improve repair. In th.s review, we summarize th. literature on reconstruction and regeneration of motor cranial nerves following various injury patterns. We focus on seven cranial nerves with.predominantly efferent functions and h.gh.igh. sh.red patterns of injuries and clinical manifestations. We also present an overview of th. existing reconstructive approach.s, from facial reanimation, laryngeal reinnervation, to variations of interposition nerve grafts for reconstruction. We discuss ongoing endeavors to promote nerve regeneration and to suppress aberrant reinnervation and th. development of synkinesis. Insigh.s from th.se studies will sh.d ligh. on recent progress and new h.rizons in understanding th. biomech.nics of periph.ral nerve neurobiology, with.emph.sis on promising strategies for optimizing

关键词： axon degeneration cranial neuropath. facial nerve facial paralysis motoneuron nerve regeneration periph.ral nerve recurrent laryngeal nerve synkinesis vocal fold paralysis

Proton pump inh.bitors and all-cause mortality risk among cancer patients

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World journal of Clinical Oncology 2025年第1期16卷 34-42页

作者： Arunkumar Krish.an Carolin Victoria schneider Declan Walsh Department of Supportive Oncology Atrium Health Levine CancerCharlotteNC 28204United States Department of Medicine Section of Hematology and OncologyWake Forest University School of MedicineWinston-SalemNC 27101United States Department of Medicine Ⅲ GastroenterologyMetabolic Diseasesand Intensive CareUniversity Hospital RWTH AachenAachen 52074Germany

BACKGROUND Proton pump inh.bitors(PPIs)are widely used,including among cancer patients,to manage gastroesoph.geal reflux and oth.r gastric acid-related *** evidence suggests associations between long-term PPI use and h.gh.r risks for various adverse h.alth.outcomes,including greater *** To investigate th. association between PPI use and all-cause mortality among cancer patients by a compreh.nsive analysis after adjustment for various confounders and a robust meth.dological approach.to minimize *** Th.s retrospective coh.rt study used data from th. TriNetX research.network,with.electronic h.alth.records from multiple h.alth.are *** study employed a new-user,active comparator design,wh.ch.compared newly treated PPI users with.non-users and newly treated h.stamine2 receptor antagonists(h.RA)users among adult cancer *** prescribed PPIs(esomeprazole,lansoprazole,omeprazole,pantoprazole,or rabeprazole)users were compared to non-users or newly prescribed h.RAs(cimetidine,famotidine,nizatidine,or ranitidine)*** primary outcome was all-cause *** patient in th. main group was match.d to a patient in th. control group using 1:1 propensity score match.ng to reduce confounding *** Cox regression models were used to estimate h.zard ratios(h.s)and 95% confidence interval(CI).RESULTS During th. follow-up period(median 5.4±1.8 years for PPI users and 6.5±1.0 years for non-users),PPI users demonstrated a h.gh.r all-cause mortality rate th.n non-users after 1 year,2 years,and at th. end of follow up(h.s:2.34-2.72).Compared with.h.RA users,PPI users demonstrated a h.gh.r rate of all-cause mortality h.:1.51(95%CI:1.41-1.69).Similar results were observed across sensitivity analyses by excluding death. from th. first 9 month. and 1-year post-exposure,confirming th. robustness of th.se *** a sensitivity analysis,we analyzed all-cause mortality outcomes between former PPI users and individual

关键词： All-cause mortality Cancer h.stamine-2 receptor antagonists Mortality Malignancy Proton pump inh.bitors Carcinoma Outcome

Lipid transport to avian oocytes and to th. developing embryo

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Th. journal of Biomedical Research 2016年第3期30卷 174-180页

作者： Wolfgang j.schneider Department of Medical Bioch.mistry Max F.Perutz LaboratoriesMedical University and Biocenter Vienna

Studies of receptor-mediated lipoprotein metabolic path.ays in avian species h.ve revealed th.t ph.siological intricacies of specific cell types are h.gh.y analogous to th.se in mammals. A prime example for th. power of com- parative studies across different animal kingdoms, elucidated in th. ch.cken, is th.t th. expression of different lipo- protein receptors in somatic cells and oocytes are th. key to oocyte growth. In avian species, yolk precursor transport from th. h.n＇s liver to rapidly growing oocytes and th. subsequent transfer of yolk nutrients via th. yolk sac to th. developing embryo are h.gh.y efficient processes. Oocytes grow from a diameter of 5 mm to 2.5-3 cm in only 7 days, and th. yolk sac transfers nutrients from th. yolk stored in th. mature oocyte to th. embryo with.n just 2 weeks. Th. underlying key transport mech.nism is receptor-mediated endocytosis of macromolecules, i.e., of h.patically synth.sized yolk precursors for oocyte growth. and of mature yolk components for embryo nutrition, respectively. Recently, th. receptors involved, as well as th. role of lipoprotein synth.sis in th. yolk sac h.ve been identified. As outlined h.re, lipoprotein degradation/resynth.sis cycles and th. expression of lipoprotein receptors are not only coordinated with.th. establish.ent of th. tbllicular arch.tecture embedding th. oocyte, but also with.th. generation of th. yolk sac vasculature essential for nutrient transfer to th. embryo.

关键词： ch.cken embryo oocyte yolk sac lipoprotein receptors vascularization

Dietary supplementation of valine,isoleucine,and tryptoph.n may overcome th. negative effects of excess leucine in diets for weanling pigs containing corn fermented protein

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journal of Animal Science and Biotech.ology 2025年第1期16卷 267-281页

作者： Andrea P.Mallea Ch.rmaine D.Espinosa Su A Lee Minoy A.Cristobal Leidy j.Torrez‑Mendoza h.ns h.Stein Division of Nutritional Sciences University of IllinoisUrbanaIL 61801USA Department of Animal Sciences University of IllinoisUrbanaIL 61801USA Present Address:EnviroFligh. RaleighNCUSA.

Background Diets with.h.gh.inclusion of corn co-products such.as corn fermented protein(CFP)may contain excess Leu,wh.ch.h.s a negative impact on feed intake and growth.performance of pigs due to increased catabolism of Val and Ile and reduced availability of Trp in th. brain for serotonin ***,we h.poth.sized th.t th. negative effect of using CFP in diets for weanling pigs may be overcome if diets are fortified with.crystalline sources of Val,Trp,and(or)*** Th.ee h.ndred and twenty weanling pigs were randomly allotted to one of 10 dietary treatments in a com-pletely randomized design,with.4 pigs per pen and 8 replicate pens per treatment.A corn-soybean meal diet and 2 basal diets based on corn and 10%CFP or corn and 20%CFP were *** additional diets were formu-lated by fortifying th. basal diet with.20%CFP with.Ile,Trp,Val,Ile and Val,Ile and Trp,Trp and Val,or Ile,Trp and Val.A two-ph.se feeding program was used,with.d 1 to 14 being ph.se 1 and d 15 to 28 being ph.se *** scores were recorded every oth.r *** samples were collected on d 14 and 28 from one pig per *** d 14,fecal samples were collected from one pig per pen in 3 of th. 10 treatments to determine volatile fatty acids,ammonium concen-tration,and microbial *** pigs were also euth.nized and ileal tissue was *** Th.re were no effects of dietary treatments on any of th. parameters evaluated in ph.se *** of 10%or 20%CFP in diets reduced(Ph. on d 28,and average daily gain(ADG)and average daily feed intake(ADFI)in ph.se 2 and for th. entire experimental ***,pigs fed th. CFP diet supplemented with.Val,Ile,and Trp h.d final body weigh.,ADFI,ADG and gain to feed ratio in ph.se 2 and for th. entire experiment th.t was not different from pigs fed th. control *** scores in ph.se 2 were reduced(P<0.05)if CFP was *** Corn fermented protein may be included by up to 20%in diets for weanling pi

关键词： Branch.d-ch.in amino acids Corn fermented protein Leucine Tryptoph.n Valine Weanling pigs